We propose to exploit the series of UNC/CH immunocytomas which have arisen in B10.H-2aH-4bP/Wts (2A4b) mice following intense antigenic stimulation. The series presently consists of 12 B-cell lymphomas (CH tumors), 6 T-cell lymphomas and 2 macrophage tumors (UNC tumors). We will explore the genetic and immunologic mechanisms which render the 2a4b strain of mice uniquely susceptible to B cell lymphoma genesis. We will study the idiotypes of the CH tumor surface immunoglobulins to test the hypothesis that they are products of a restricted spectrum of VH genes and will explore the general usefulness of anti-idiotype reagents for management and immunotherapy of these B-cell lymphomas. Using computer assisted analysis of flow cytometry data resulting from testing with specific antisera and monoclonal antibodies we will describe the pattern of differentiation antigens expressed by the cells of each tumor, will determine the clonality of the primary tumors and will study the potentials for consequences of spontaneous and induced differentiation of the CH series of B cell lymphomas.